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SUMMARY Hormonal dysfunction involving the hypothalamic-pituitary-adrenal (HPA) axis, prolactin (PRL) secretion and sex hormone status has been supposed to contribute to the development or persistence of rheumatoid arthritis (RA). In addition, a reduced number of glucocorticoid receptors on circulating lymphocytes has been found in patients with RA. However, so far most studies have been performed in pre-treated patients. A combined test for total anterior pituitary reserve was performed in 10 patients with newly diagnosed untreated RA. Before and after stimulation with the respective hypothalamic releasing hormones, RA patients showed no difference in plasma concentrations of adrenocorticotrophic hormone (ACTH), cortisol, prolactin (PRL) and thyroid-stimulating hormone (TSH) when compared to healthy controls. In contrast, the growth hormone (GH) response to growth hormone-releasing hormone (GHRH) was blunted in RA patients. The hypothalamic-pituitary-thyroid/gonadal and adrenal axes seem to be unaltered in RA. However, if one considers the presence of chronic inflammation, normal plasma ACTH and cortisol concentrations must be considered as inappropriately low. The observed blunted GH release could be mediated by cytokines (e.g. IL-1), which are known to be elevated in RA. [ABSTRACT FROM PUBLISHER]

Recurrent arthritis, fever and lymphadenopathy are symptoms of adult onset of Still's disease (AOSD). Differential diagnosis requires the exclusion of infections or malignant lymphomas. We report on a case of AOSD showing destructive lymphadenopathy, immunophenotyping of peripheral blood leucocytes revealed strong activation of T-lymphocytes. Bone marrow biopsy also showed an increase of lymphopoietic cells to 23%. Analysis of peripheral blood lymphocytes (PBL) after remission showed no remaining signs of activation. Analysis of lymphocyte activation by flow cytometry correlated with disease activity. [ABSTRACT FROM PUBLISHER]

Rheumatoid arthritis is characterised by pain, swelling, and destruction of joints, with resultant disability. Only disease-modifying antirheumatic drugs can interfere with the disease process. In the past few years, biological agents, especially inhibitors of tumour necrosis factor, have allowed for hitherto unseen therapeutic benefit, although even with these drugs the frequency and degree of responses are restricted. Therefore, new agents are needed, and three novel biological compounds for treatment of rheumatoid arthritis have already been used in practice or are on the horizon: rituximab (anti-CD20), abatacept (cytotoxic T-lymphocyte antigen 4 immunoglobulin), and tocilizumab (anti-interleukin 6 receptor). We discuss the targets of these drugs, the roles of these targets in the pathogenesis of rheumatoid arthritis, and the efficacy and adverse effects of these agents from clinical trial data. Novel therapeutic strategies in conjunction with optimised disease assessment for better treatment of rheumatoid arthritis and an outlook into potential future targets are also presented. [ABSTRACT FROM AUTHOR]

Beall's list is widely used to identify potentially predatory journals. With this study, we aim to investigate the impact of Beall's list on the perception of listed journals as well as on the publication and citation behavior of the scientific community. We performed comprehensive bibliometric analyses of data extracted from the ISSN database, PubMed, PubMed Central (PMC), Crossref, Scopus and Web of Science. Citation analysis was performed by data extracted from the Crossref Cited-by database. At the time of analysis, Beall's list consisted of 1,289 standalone journals and 1,162 publishers, which corresponds to 21,735 individual journals. Of these, 3,206 (38.8%) were located in the United States, 2,484 in India (30.0%), and 585 in United Kingdom (7.1%). The majority of journals were listed in the ISSN database (n = 8,266), Crossref (n = 5,155), PubMed (n = 1,139), Scopus (n = 570), DOAJ (n = 224), PMC (n = 135) or Web of Science (n = 50). The number of articles published by journals on Beall's list as well as on the DOAJ continuously increased from 2011 to 2017. In 2018, the number of articles published by journals on Beall's list decreased. Journals on Beall's list were more often cited when listed in Web of Science (CI 95% 5.5 to 21.5; OR = 10.7) and PMC (CI 95% 6.3 to 14.1; OR = 9.4). It seems that the importance of Beall's list for the scientific community is overestimated. In contrast, journals are more likely to be selected for publication or citation when indexed by commonly used and renowned databases. Thus, the providers of these databases must be aware of their impact and verify that good publication practice standards are being applied by the journals listed., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Richtig et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: older people remain underrepresented in clinical trials, and evidence generated in younger populations cannot always be generalized to older patients., Objective: to identify key barriers and to discuss solutions to specific issues affecting recruitment and retention of older participants in clinical trials based on experience gained from six current European randomised controlled trials (RCTs) focusing on older people., Methods: a multidisciplinary group of experts including representatives of the six RCTs held two networking conferences and compiled lists of potential barriers and solutions. Every item was subsequently allocated points by each study team according to how important it was perceived to be for their RCTs., Results: the six RCTs enrolled 7,612 older patients. Key barriers to recruitment were impaired health status, comorbidities and diverse health beliefs including priorities within different cultural systems. All trials had to increase the number of recruitment sites. Other measures felt to be effective included the provision of extra time, communication training for the study staff and a re-design of patient information. Key barriers for retention included the presence of severe comorbidities and the occurrence of adverse events. Long study duration, frequent study visits and difficulties accessing the study site were also mentioned. Solutions felt to be effective included spending more time maintaining close contact with the participants, appropriate measures to show appreciation and reimbursement of travel arrangements., Conclusion: recruitment and retention of older patients in trials requires special recognition and a targeted approach. Our results provide scientifically-based practical recommendations for optimizing future studies in this population., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

We prospectively performed a longitudinal analysis of circulating tumor DNA (ctDNA) from 149 plasma samples and CT scans in Stage III and IV metastatic melanoma patients ( n = 20) treated with targeted agents or immunotherapy using two custom next-generation sequencing (NGS) Ion AmpliSeq™ HD panels including 60 and 81 amplicons in 18 genes, respectively. Concordance of matching cancer-associated mutations in tissue and plasma was 73.3%. Mutant allele frequency (MAF) levels showed a range from 0.04% to 28.7%, well detectable with NGS technologies utilizing single molecule tagging like the AmpliSeq™ HD workflow. Median followup time of the tissue and/or plasma positive cohort ( n = 15) was 24.6 months and median progression-free survival (PFS) was 7.8 months. Higher MAF ≥ 1% at baseline was not significantly associated with a risk of progression (Odds Ratio = 0.15; p = 0.155). Although a trend could be seen, MAF levels did not differ significantly over time between patients with and without a PFS event ( p = 0.745). Depending on the cell-free DNA amount, NGS achieved a sensitivity down to 0.1% MAF and allowed for parallel analysis of multiple mutations and previously unknown mutations. Our study indicates that NGS gene panels could be useful for monitoring disease burden during therapy with ctDNA in melanoma patients.

The transfer of genetic information into living cells is a powerful tool to manipulate their protein expression by the regulation of protein synthesis. This can be used for the treatment of genetically caused diseases (gene therapy). However, the systemic application of genes is associated with a number of problems, such as a targeted gene delivery and potential side effects. Here we present a method for the spatial application of nanoparticle-based gene therapy. Titanium was electrophoretically coated with DNA-functionalized calcium phosphate nanoparticles. NIH3T3 cells and HeLa cells were transfected with pcDNA3-EGFP. We monitored the transfection in vitro by fluorescence microscopy, flow cytometry, and Western Blot analysis. By coating a transparent substrate, i.e., indium tin oxide (ITO), with nanoparticles, we followed the transfection by live cell imaging.

Sarcomas display a rare and heterogeneous group of tumors. Treatment options are limited. Host defense peptides (HDPs), effector molecules of the innate immune system, might provide a more effective treatment option. The aim of our study was to analyze the oncolytic activity and mode of action of a designer HDP. In vitro, the human liposarcoma cell line SW-872 and primary human fibroblasts as a control were exposed to [D]-K(3)H(3)L(9), a 15-mer D,L-amino acid designer peptide. Cell growth (MTT assay), proliferation (BrdU assay) and genotoxicity (TUNEL assay) were analyzed. The mode of action was examined via fluorescence-activated cell sorter (FACS) analysis and confocal laser scanning microscopy. In vivo, [D]-K(3)H(3)L(9) (n = 7) was administered intratumorally in a SW-872 xenograft mouse model (Foxn1nu/nu). Phosphate buffered saline served as a control (n = 5). After 4 weeks, tumor sections were histologically analyzed with respect to proliferation, cytotoxicity, vessel density and signs of apoptosis and necrosis, respectively. In vitro, [D]-K(3)H(3)L(9) highly significantly (p < 0.01) inhibited cell metabolism and proliferation. TUNEL assay revealed corresponding genotoxicity. FACS analysis suggested induction of necrosis as a cause of cell death. The mean tumor volume of the control group exponentially increased sevenfold, whereas the mean tumor growth was negligible in the treatment group. Macroscopically, [D]-K(3)H(3)L(9) induced full tumor remission in 43% of treated animals and partial remission in 43%. Vessel density was significantly reduced by 52%. Morphological analyses supported the hypothesis of cancer cell killing by necrosis. In summary, [D]-K(3)H(3)L(9) exerts very promising oncolytic activity on liposarcoma cells. Our study demonstrates the potential of HDPs as a novel therapeutic option in future soft tissue sarcoma therapy., (Copyright © 2010 UICC.)

This study describes the collagen-I coating of titanium and steel implants via cold low-pressure gas plasma treatment. To analyze the coatings in terms of biocompatibility osteoblast-like osteosarcoma cells and human leukocytes were cultivated on the metal surfaces. Two different implant materials were assessed (Ti6Al4V, X2CrNiMo18) and four different surface properties were evaluated: (a) plasma pretreated and collagen-I coated implant materials; (b) collagen-I dip-coated without plasma pretreatment; (c) plasma treated but not collagen-I coated; (d) standard implant materials served as control. The different coating characteristics were analyzed by scanning electron microscopy (SEM). For adhesion and viability tests calcein-AM staining of the cells and Alamar blue assays were performed. The quantitative analysis was conducted by computer assisted microfluorophotography and spectrometer measurements. SEM analysis revealed that stable collagen-I coatings could not be achieved on the dip-coated steel and titanium alloys. Only due to pretreatment with low-pressure gas plasma a robust deposition of collagen I on the surface could be achieved. The cell viability and cell attachment rate on the plasma pretreated, collagen coated surfaces was significantly (p < 0.017) increased compared to the non coated surfaces. Gas plasma treatment is a feasible method for the deposition of proteins on metal implant materials resulting in an improved biocompatibility in vitro. (c) 2010 Wiley Periodicals, Inc. J Biomed Mater Res, 2010.

There is controversy about the origin of the alterations in T helper 1 (TH1)/TH2 cell activity after major surgical procedures such as on-pump cardiac surgery. We hypothesized that a postoperative decrease in interferon (IFN) gamma-producing TH1 lymphocyte activity may be the sole cause of this TH1/TH2 shift and that the addition of recombinant IL-12 can reverse TH1 suppression. Peripheral blood mononuclear cell fractions from 20 low-risk elective cardiac surgery patients were analyzed preoperatively (d0) and on the first (d1), third (d3), and sixth (d6) postoperative days. We determined the absolute numbers of T helper lymphocytes, IFN-gamma-producing TH1 cells, and IL-4-producing TH2 cells after stimulation and measured IFN-gamma and IL-4 levels in the supernatants of stimulated peripheral blood mononuclear cell cultures, absolute monocyte counts, human leukocyte antigen-DR expression, and intracellular IL-12 synthesis under comparable conditions. Recombinant IL-12 alone or in combination with a neutralizing antibody was added. T helper lymphocyte counts were reduced postoperatively from d1 to d6 (P < 0.05). Absolute IFN-gamma- and IL-4-positive T helper lymphocyte counts were reduced on d1 (P < 0.05). Intracellular IL-4 production in T helper lymphocytes remained postoperatively unchanged. Interferon gamma synthesis was significantly reduced until d3 (P = 0.001) and significantly increased after IL-12 addition (P < 0.05). This effect was reversed by the addition of a neutralizing anti-IL-12 antibody. The TH1/TH2 shift after cardiac surgery seems to be caused primarily by a decrease in cellular IFN-gamma synthesis in TH1 lymphocytes. Because TH1 suppression can be reversed by IL-12, it is more likely to be the result of altered stimulation pathways than cellular defects.

Background: Major trauma induces a dysregulation of immune response supported in parts by lymphocyte dysfunction. Controversial data about a shift within the T-helper cell subsets Th1/Th2 are reported., Methods: To prove whether Th1/Th2-type cytokine plasma levels reflect the postulated Th2 shift after trauma, we investigated in a retrospective study 195 severely injured patients (47 women, 148 men; mean age 39.7 +/- 15.8 years; Injury Severity Score 32.0 +/- 11.3 points; overall 1,887 samples) during their ICU stay posttrauma. Mortality rate was 19%. Th1-type cytokines interleukin 2 (IL-2), interferon gamma, IL-12 (p70), and IL-18 and Th2-type cytokines IL-4, IL-10, and IL-11 were determined using the enzyme-linked immunosorbant assay technique in patients and in healthy controls., Results: IL-2 and interferon gamma were seldom detectable. All other mediators were significantly increased matched to controls (p < 0.05). All cytokines were elevated most prominent during weeks 1 and 2 posttrauma and declined thereafter. A trend toward lower levels in nonsurvivors was seen for both groups of cytokines. However, significant differences were only seen for Injury Severity Score, age, white blood cells, and C-reactive protein. All mediators correlated positively with each other (p < 0.01), a Th2-type shift was not observed. Two groups of patients were identified: one group with generally high plasma levels of all cytokines investigated and a second group of nonresponders who presented with low or diminished plasma levels in which most nonsurvivors were found., Conclusion: We conclude that in plasma no Th1/Th2 shift can be observed after major trauma.

Background: Despite low-dose gluco-corticoid (GC) treatment, many patients with rheumatoid arthritis (RA) require additional flare therapy with GC at higher doses. Since low dose GC has been suggested to confer resistance to higher doses, we aimed to assess if resistance was detectable on the clinical level in patients with active RA., Methods: Eighty-nine patients with active RA (Disease Activity Score 28, DAS28>3.2; mean age 54.5 years, mean duration of RA 9.7 years) were consecutively enrolled into a one-week trial of a total of 250 mg prednisolone. We compared improvement of the DAS28 and the Simplified Disease Activity Index (SDAI) in groups of patients with (n=41) and without (n=48) low-dose GC at baseline (by t-test). In addition, we analyzed changes of all individual core set measures of disease activity using multivariate statistics., Results: All clinical, serological and functional measures improved significantly over one week (p<0.001). Baseline RA activity of patients with and without low-dose GC was on average +/- standard deviation similar among the two groups (DAS28: 4.8+/-1.2 and 4.9+/-1.1; mean SDAI: 26.1+/-14.0 and 25.9+/-13.0, respectively), and likewise there was no difference between the two groups in the final disease activity reached, for both the DAS28 (1.4+/-1.1 vs. 1.1+/-1.0; p=0.14) and the SDAI (11.1+/-13.4 vs. 11.1+/-11.4; p=0.99). Improvement in all individual measures was also not different using a multivariate model (p=0.26)., Conclusion: Pre-treatment with low-dose GC does not appear to portend GC resistance at least clinically, since the responsiveness to GC boosts is unaffected.

Increasing evidence underlines the substantial pathophysiological impact of platelets on the development of ischemia/reperfusion injury (I/R) in flaps. Methods for studying dynamic platelet mechanisms in flaps in vivo are not available. The aim of this study was to develop a model enabling quantitative analysis of platelet kinetics and platelet-endothelium cell interaction within the microcirculation of muscle flaps in vivo. Balb/c mice (n = 16) were anesthetized, and an epigastric muscle flap was prepared. Autologous platelets were separated from blood donor animals (n = 16) and labeled ex vivo by means of rhodamine-6-G. After I/R (90 minutes' clamping, 10 minutes' reperfusion), the platelets were administered intra-arterially (i.a.). Microhemodynamics and kinetics of platelets were investigated by intravital fluorescence microscopy. I/R of muscle flaps induced disturbances in microcirculation. The number of rolling platelets, as well as platelets adhering to the inner vessel wall of venules, was increased in the ischemia group. Using intravital fluorescence microscopy, platelet kinetics were analyzed directly in flap microcirculation in vivo for the first time. Since platelet/endothelial cell interaction is a key event in the pathophysiology after microsurgical procedures, this model will help to understand basic molecular mechanisms of platelet behavior during I/R.

Objective: To characterize clinical and pathologic characteristics of sarcomatoid carcinoma of the cervix., Methods: We retrospectively reviewed the charts of women with sarcomatoid carcinoma of the cervix identified by query of the Snomed pathologic diagnostic retrieval system and by direct physician query. Data were extracted from available charts, and pathology review was performed on all cases. SPSS was used for statistical analysis., Results: Nine of 12 identified patients had complete clinical information and pathologic material available. The mean age at diagnosis was 48 (range, 29-76) years. Stage at diagnosis was I (4 patients), II (2 patients), and IV (3 patients). Patients younger than 40 years of age presented with stage I disease. All patients had visible tumor; 8 of 9 had vaginal bleeding or discharge at presentation. Microscopic evaluation revealed areas of spindle-cell sarcomatous tumor confluent with areas of poorly differentiated squamous cell carcinoma. Immunohistochemistry demonstrated coexpression of cytokeratin and vimentin in tumor cells. Tumors with a prominent spindle-cell component also expressed smooth muscle actin. Initial treatment varied, but all patients had a complete response to initial treatment. Five patients recurred with a median disease-free interval of 4.9 (range, 2-9.5) months, and none responded to second-line therapy. Four patients remained disease-free at 5, 18, 30, and 40 months, respectively, after completing initial therapy., Conclusions: Sarcomatoid carcinoma of the cervix is an aggressive neoplasm. Primary treatment offers the best chance for cure in women with early-stage disease. Patients with advanced disease at presentation or recurrence succumb to their disease.

Markers of bone turnover are often elevated in patients with prevalent bone metastases (BM). To test whether bone markers may be used as early indicators of developing BM, we prospectively studied 113 women with primary breast cancer. At the time of study inclusion, none of the women had BM, skeletal disease or was on bone active drugs. During follow-up (8-52, median 30 mo.), pt. were seen every 3 mo. and blood/urine specimens were obtained. Eleven patients developed BM (BM+) and each of them was matched to 4 women remaining free of BM (BM-). Markers were serum (s) calcium, sTAP, sBAP, sOC, sPICP, sNTX, sCTX and urinary (u) PYD, uDPD, uNTX, uCTX. All analyses were done in single batches after study end. At any given point in time, marker levels in the BM+ group did not differ from those in the BM- group. Levels at baseline did not predict later BM (OR 0.14-1.01, all ns). 93% of all changes in bone markers were below the least significant change, as defined in an independent group of similar patients. The remaining 7% of values could not be associated in a consistent pattern with the occurrence of BM. We conclude that in patients with primary breast cancer, biochemical markers of bone turnover can not be used to predict or diagnose incident BM. This lack in diagnostic validity is mainly attributable to the high overall and long-term variability of the currently used bone markers.

Variability of bone marker measurements is a major problem in their clinical application. Most studies on marker variability have been performed in healthy subjects and over relatively short intervals of time. We prospectively evaluated the long-term variability of bone markers in 102 postmenopausal women diagnosed with primary breast cancer. During follow up (8-48, median 30 mo.), no patient developed bone metastases or other skeletal disease. Patients were seen every 3 months and exactly timed blood/urine specimens were obtained. All analyses were performed after study end by the same technician, using a single batch of reagents per analyte. The coefficient of variation was calculated as CV (%) = square root(sigma(CVi2)/n) (CVi = SD/mean x 100; n = n of CVi). The least significant change (LSC) was then LSC (%) = Z x CV x square root(2). Z = 1.96 for a 95% confidence interval (LSC-95). In a subset of n = 10 patients with no potential interference during follow-up, lowest CVs were recorded for serum (s) calcium (5%), sTAP (12%) and sBAP (14%). The LSC-95 for these markers were 14%, 33% and 39%, respectively. Highest CVs were seen with urine (56%) and serum (42%) CTX (LSC-95: 155%, 117% resp.). We conclude that in breast cancer patients without bone metastases, long-term variability varied greatly between markers. For certain markers, the LSC seems considerably higher than previously reported.

Recipients of lung transplants are at very high risk for significant bone loss. Nevertheless, data on bone disease after lung transplantation are still limited. We, therefore, retrospectively evaluated the data of 33 patients surviving at least 1 year after lung transplantation (LTx) who were seen in our outpatient clinic for osteologic evaluation. Results of clinical evaluations, radiographs, and dual-energy X-ray absorptiometry (DXA) were related to each other, to clinical variables, and to serum levels of osteocalcin, parathyroid hormone (PTH), and 25-hydroxyvitamin D: 14 of 33 patients (42%) had vertebral fractures, 9 of whom were diagnosed within 2 years after transplantation. Bone mineral density values (DXA) were markedly decreased and predictive of compression fractures. 25-Hydroxyvitamin D levels were low in 13 patients (39%) and PTH was elevated in 7 (21%). Despite corticosteroids and low 25-hydroxyvitamin D, serum osteocalcin was elevated in 12 patients (36%). This was only partially explained by hyperparathyroidism, low sex hormones, and impaired renal function, and may partly be caused by cyclosporin A. We thus conclude that severe symptomatic bone disease is common in lung transplant recipients and due to a complex situation including high turnover bone loss and hypovitaminosis D. DXA can be used to estimate fracture risk for individual patients.

We developed a method using a single set of degenerate oligonucleotide primers for amplification of the conserved active site of transglutaminases by reverse transcription-polymerase chain reaction (RT-PCR) and identification of the PCR products by cleavage with diagnostic restriction enzymes. We demonstrate amplification of tissue transglutaminase (TGC), keratinocyte transglutaminase (TGK), prostate transglutaminase (TGP), the a-subunit of factor XIII, and band 4.2 protein from different human cells or tissues. Analysis of normal human keratinocytes revealed expression of a transglutaminase different from the expected and characterized transglutaminase gene products. A full-length cDNA for the novel transglutaminase (TGX) was obtained by anchored PCR. The deduced amino acid sequence encoded a protein with 720 amino acids and a molecular mass of approximately 81 kDa. A comparison of TGX to the other members of the gene family revealed that the domain structure and the residues required for enzymatic activity and Ca2+ binding are conserved and showed an overall sequence identity of about 35%. Two transcripts with an apparent size of 2.2 and 2.8 kilobases were detected with a specific probe for TGX on Northern blots of human foreskin keratinocyte mRNA, indicating the presence of alternatively spliced mRNAs. cDNA sequencing revealed a shorter TGX transcript lacking the sequence homologous to that encoded by exon III of other transglutaminase genes. TGX expression increased severalfold when keratinocyte cultures were induced to differentiate by suspension or growth to postconfluency, suggesting that TGX contributes to the formation of the cornified envelope.

Spontaneous growth of myeloid colonies (colony-forming unit-granulocyte-macrophage [CFU-GM]) can be observed in methylcellulose cultures containing peripheral blood mononuclear cells (PB-MNCs) and is supposedly caused by the release of colony-stimulating factors (CSF) by accessory cells. Because of its cytokine synthesis-inhibiting effects on T lymphocytes and monocytes, interleukin-10 (IL-10) may be a potential candidate for indirect modulation of hematopoiesis. We studied the effect of recombinant human IL-10 (rhIL-10) on spontaneous growth of myeloid colonies derived from human PB-MNCs. A total of 10 ng/mL of IL-10 almost completely inhibited spontaneous CFU-GM proliferation (by 95.1%; P < .001, n = 7) in unseparated PB-MNCs. This effect was dose-dependent and specific, because a neutralizing anti-IL-10 antibody was able to prevent IL-10-induced suppression of CFU-GM growth. Spontaneous CFU-GM growth, which required the presence of both monocytes (CD14+ cells) and T lymphocytes (CD3+ cells), was also greatly suppressed by a neutralizing anti-granulocyte-macrophage CSF (GM-CSF) antibody but was only slightly or not at all inhibited by antibodies against G-CSF or IL-3. Moreover, IL-10-suppressed colony growth could be completely restored by the addition of exogenous GM-CSF. Using semiquantitative polymerase chain reaction, we were able to show that GM-CSF transcripts that spontaneously increased in PB-MNCs within 48 hours of culture were markedly reduced by the addition of IL-10. Inhibiton of GM-CSF production in PB-MNCs by IL-10 was also confirmed at the protein level by measuring GM-CSF levels in suspension cultures. Our findings suggest that autonomous CFU-GM growth, resulting from an interaction of monocytes and T lymphocytes, is mainly caused by endogenous GM-CSF release and can be profoundly suppressed by the addition of exogenous IL-10. Considering the strong inhibitory action of IL-10 on GM-CSF production and spontaneous cell growth in vitro, this cytokine may be useful in myeloid malignancies in which autocrine and/or paracrine mechanisms involving GM-CSF are likely to play a pathogenetic role.